A conventional screen is proposed having a less expandable or mainly metal mesh provided as an image forming portion at a center thereof, and another mesh of a larger size provided about the image forming portion which is greater in terms of elasticity than the image forming portion (Japanese Utility Model Application Publication (JP-Y) No. 51-9297). More specifically, two types of mesh which are different in terms of expandability are joined together to construct the screen. In similar respects, another screen is known having a stainless steel mesh provided as an image forming portion and surrounded by a polyester mesh. Also, a further screen structure is known having an image forming portion located not at a center but biased in an upper, lower, left, or right direction (Japanese Patent Application Laid-open (JP-A) No. 2-00494).
As having at least two meshes overlapped, a combination mask is proposed where an edge of a metal sheet having imaging perforations of a printing surface is implemented by these two overlapped meshes (JP-A No. 9-150497).
Another is proposed having one mesh provided with a reinforcement between a frame and an image forming portion. The reinforcement is a sheet material or is made by curing an adhesive (JP-A No. 11-170719).
Some screens of a mesh and sheet combined type are known having a stainless steel mesh provided as an image forming portion and surrounded by a polyester film.